Most forced warm air central heating systems utilize a standard furnace to heat air which is heated within a heat exchanger and forced through duct work to areas which the furnace is to heat. Generally, this operation is based upon receiving a control signal from a thermostat which is mounted in a remote location; normally, in the area which is to be heated. The thermostat sends a control signal to the furnace and turns the furnace on or off based upon the ambient air temperature of the room which is heated. In this manner, the furnace cycles on and off, sending heated forced air to the space which is heated. Most furnaces, however, operate at a fuel input rate which provides significantly more heat than is necessary. In residential use, most furnaces are designed to heat an entire house in a short period of time. These furnaces are designed such that they may bring a house from a temperature well below the desired temperature to the desired temperature rapidly. When a furnace is being utilized strictly for the purpose of maintaining a specific temperature within a house, which is the normal function of a furnace, most furnaces are operating at, or about, 75% above the necessary fuel input level and, therefore, energy may be wasted. The object of this invention is to increase energy efficiency and provide improved temperature control (comfort) in the heated space.